Abstract:Listening devices, tracking devices, and other covert implants have to send any data they collect to a central command and control (C&C) server. This task can be difficult, since implants typically have a restricted power budget and cannot connect directly to the Internet. Several works have attempted to exfiltrate data in this setting by taking advantage of a nearby networked device, such as a computer or a mobile phone. To achieve this, the implant uses a covert channel to send the data to the networked device, that performs the exfiltration. Several constructions have been proposed for this covert channel between implant and target device, using sensors such as the microphone, magnetometer and gyroscope.